Fuzzy logic with the Taguchi method is proposed for estimating submerged-arc welding design parameters. Design of experiments based on simulation applied to approach. The finite element analysis a steel plate carried out simulate process using thermomechanical and temperature-dependent material properties. Welding results thermal–mechanical coupled physical phenomena are compared test. fuzzy model generated triangle membership functions if–then rules training data obtained from method....

The paper deals with the strength design of an automotive knuckle component under bump and brake loading conditions. problem is formulated such that cross-sectional sizing variables are determined by minimizing weight a subject to stresses, deformations, frequency constraints. initial model generated on basis actual vehicle specification. finite element analysis conducted using ABAQUS, optimal solutions obtained via moving least-squares method (MLSM) in context response-surface-based...

본 논문에서는 범프 및 브레이크 하중조건 하에서 자동차 넉클의 강도설계에 관한 다양한 회귀모델 기반근사최적화 기법 그 성능을 비교하고자 한다. 최적설계문제는 응력, 변형 진동주파수의 제한조건 중량을 최소화하여 설계변수인 단면치수가 결정되도록 정식화 된다. 비교 연구를 위해 사용된 근사화 기법은 순차적 근사최적화(SAO), 이점대각이차 근사최적화(STDQAO), 그리고 개선된 이동최소 자승법(MLSM) 기반 근사최적화 기법인 CF-MLSM 와 Post-MLSM 이다. SAO STDQAO 적용을 위하여 상용프로세스통합 설계최적화(PIDO) 코드를 사용하였다. 연구에 적용한 MLSM 기법들은 제한조건의 가용성을 보장할 수 있도록 새롭게 개발되었다. 기법에 의한 설계결과는 설계 해의 개선 수렴속도등 수치적 기준으로 실제 비근사최적화 결과와 비교검토 되었다.

Most yacht sails are made of thin fabric, and they have a cambered shape to generate lift force; however, their can be easily deformed by wind pressure. Deformation the sail changes flow characteristics over sail, which in turn further deforms shape. Therefore, fluid-structure interaction (FSI) analysis is applied for precise evaluation or optimization design. In this study, fluid analyses performed main 30-foot yacht, results loading conditions structural analyses. By applying supporting...

In the case of a fire accident on ship or an offshore plant, design bulkhead penetration piece must be verified via test procedure (FTP), as specified by Maritime Safety Committee (MSC). The purpose this study is to verify both numerical analysis results and specifications for pieces that could applied A60 class division. study, FTP was carried out in accordance with prescribed MSC regulation. order review resistance performance according material type, were made from brass, carbon steel...

This study provides a comparative analysis of experiments-based enhancements and sensitivity evaluations for the structural design an automatic ocean salt collector under various load conditions. The sizing variables members were considered as factors. strength weight performances selected output responses. experiments used in consisted orthogonal array design, Box–Behnken central composite design. response surface model, one metamodels, was applied to approximate model generation....

The response surface method (RSM) and the moving least squares (MLSM) are extensively used due to their computational efficiency in solving reliability based design optimization (RBDO) problems. Since traditional RSM MLSM described by second-order polynomials, approximated constraints sometimes unable ensure feasibility when highly nonlinear and/or nonconvex constraint functions RBDO. We explore development of a new meta-model that ensures an optimal solution A constraint-feasible (CF-MLSM)...

Recently, problems with excessive vibration of the radar masts large bulk carriers and crude oil tankers have frequently been reported. This paper explores a design method to avoid resonance mast installed on ship using various experiment (DOE) methods. A local test was performed during an actual sea trial determine excitation sources related resonant frequency mast. DOE methods such as orthogonal array (OA) Latin hypercube (LHD) were used analyze Pareto effects vibration. In these methods,...

A60 class bulkhead penetration piece is a fire-resistance apparatus installed on compartments to protect lives and prevent flame diffusion in case of fire accident ships offshore plants. In this study, approximate optimization with discrete variables was carried out for the design an (A60 BPP) using various meta-models multi-island genetic algorithms. Transient heat transfer analysis evaluate piece, we verified results via test. The experiment’s method applied generate be used optimization,...

This paper presents a structural design review of marine loading arm used for the fluid transfer liquid cargo from ship or offshore plant. The is installed on ship, plant, jetty in order to load unload such as crude oil, liquefied natural gas (LNG), chemical products, etc. this obliged comply with and construction specifications regulated by oil companies international forum (OCIMF). In paper, safety initial evaluated conditions required various operational modes. results based finite...

The paper deals with comparative study of various surrogate models based approximate optimization in the structural design passive type deck support frame under load conditions. was devised to facilitate both transportation and installation 20,000 ton class topside. Structural analysis performed using finite element method evaluate strength performance its initial stage. In analysis, performances were evaluated for optimum problem on model formulated such that thickness sizing variables main...

This study aims to identify the optimal welding conditions for laser hybrid on a 5052-H32 aluminium alloy. Non-linear transient thermal analysis is adopted simulate thermo-physical phenomena in process. Taguchi's parameter design method applied establish parameters that minimize residual stress and strain. The results obtained via of experiments (DOE) using simulations are compared with experimental results. Using DOE data, approximation models such as polynomial-based response surface...

This article addresses the approximate multi-objective optimum design of an automotive hydraulic steering system based on a multi-body dynamics analysis. The problem was formulated to determine dimensions mechanism that is able estimate Pareto-optimal solutions weight and vibration frequencies are subject dynamic response constraints main components. were calculated using non-dominated sorting genetic algorithm-II (NSGA-II) various models, reviewed in terms exploration performance constraint...

Since most of yacht sails are made thin fabric, they form cambered sail shape that can efficiently generate lift power by aerodynamic interaction and external force delivered from supporting structures such as mast boom. When the incident flow alter in terms volume or condition, also change. This deformation has impact on peripheral sail, thus it is related to again. Therefore, precise optimization performance requires fluid-structure (FSI) analysis. In this study, simplified without camber...

Paragonimus westermani, the lung fluke, is known to migrate pulmonary tissue of mammalian hosts and causes pathological changes in lungs. An acidic thiol-dependent proteinase with a molecular weight approximately 20,000 daltons was purified homogeneity using ion-exchange chromatography gel filtration chromatography. On SDS-PAGE, enzyme 17,500 daltons. Isoelectric point 6.45. The similar cysteine vertebrates properties pH 5.5 for at least two days when stored 4 degrees C. capable degrading...